Most American women should get fewer breast cancer screening mammograms and start them at a later age than previously recommended, a government-appointed panel of health experts advised in the Nov. 17 issue of the Annals of Internal Medicine.

Healthy women should get routine screening mammograms every two years — not annually — and they should start at age 50, not 40, the U.S. Preventive Services Task Force, an influential government-sponsored panel of medical experts, recommended. Nor should doctors teach patients to do monthly breast self-examinations (BSE) to look for lumps and changes.

The new guidelines drew mixed response from medical experts.

The American Cancer Society is sticking to its recommendation for annual mammograms starting at age 40.

“With its new recommendations, the [task force] is essentially telling women that mammography at age 40 to 49 saves lives; just not enough of them,” said Dr. Otis W. Brawley, chief medical officer of the American Cancer Society.

“There has never been data supporting the use of mammography screening in women under 50,” Dr. Love said in exclusive remarks emailed to Lifescript.com. “Estimates of the radiation risk suggest that under-40 regular mammograms would cause more cancers from the radiation than they cure. Between 40 and 50, it’s a wash – about the same number caused and cured; and after 50 [there’s] more benefit than risk.”

The dust-up leaves women to wonder: What should they do to protect their breast health? There’s no clear answer.

Modifying its 2002 report, which recommended that women get a screening mammogram every 1-2 years, the task force said that biennial screenings are nearly as effective as annual ones and reduce the potentially harmful effects of mammography by nearly half.

That includes false-positive results, in which a mammogram shows a suspicious change in the breast but no cancer is found in later tests. That can lead to anxiety and extra costs of unwarranted imaging and biopsies, says Diana B. Petitti, M.D., vice chair of the task force.

Among the other harmful effects the report mentioned:

Overtreatment of slow-growing cancers that would not have resulted in death

Radiation exposure (from radiologic tests), although a minor concern

The task force said new research showed that women 40-49 years old see only a small “net benefit” from routine mammograms.

They’re less likely to have their lives saved by screening mammograms than older women, the panel explained, but they’re more likely to undergo extra biopsies and procedures that can result from false-positive mammograms.

But the task force emphasized that its new advice was for women of average risk, not those at higher risk for breast cancer, including those with genetic traits or a history of chest radiation. The report didn’t make official screening recommendations for them.

Nor did it offer advice for those with the denser breasts, common in younger women, which can interfere with the accuracy of mammograms.

“This is not a recommendation against screening women who are in their 40s,” Petitti added. “It’s a recommendation against routine screening ... screening that takes place [without] a discussion about the benefits and harms [negatives].”

Love said she has never recommended it for women under 50 and blamed “pressure” from radiologists and Congress for prior endorsements of the practice.

Almost as notable as what the task force recommended was what it didn’t: In its recommendation against teaching breast self-exam, it said “adequate evidence suggests that teaching BSE does not reduce breast cancer mortality.”

"Both Love and the American Cancer Society said that there is not enough evidence to recommend that women do BSE. But Love explained that the task force's recommendation doesn't mean that women shouldn't informally take note of changes in their breasts."

“The data is clear that poking around is as good as formal BSE,” she said. “What the recommendations say is that doctors shouldn’t spend time teaching women formal BSE, not that women should stop touching their breasts.”

In other findings, the government task force said that current evidence is insufficient to assess:

The effectiveness of screening mammography for women age 75 and up: Although randomized clinical trials on breast-cancer screenings haven’t included such women, they may benefit less from screening than others and even be harmed by treatment for slow-growing cancers that might not be fatal, the panel said.

The American Cancer Society, on the other hand, says, “There’s no specific upper age at which mammography screening should be discontinued.”

Whether digital mammography is better than film: The procedure can cost more and some experts say it’s superior to regular film mammography. But the task force said film mammography appears to detect some cancer cases that digital doesn't detect, and vice versa.

The effectiveness of clinical breast exam: Whether it’s valuable to add CBE, in which a health professional physically examines a woman’s breasts, to regular mammograms. Besides potentially causing unwarranted anxiety and worry, such exams aren’t governed in the U.S. by a standard approach or reporting standards, the panel complained.

The American Cancer Society agrees that the quality of CBE needs to be improved, but says it’s still worthwhile because of evidence indicating that some cancers detected by CBE weren’t detected by mammography.

What’s Your Breast Cancer Risk?The biggest risk factor for developing breast cancer is simply being a woman, though a small percentage of men develop it, too. Find out how at-risk you are with this breast cancer quiz.

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